The invention relates to an automatic pencil cartridge which, like a refill of a ball-point pen, can be placed in a pencil body, and particularly to a cartridge that can be fitted in pencil bodies having different shapes.
In prior automatic pencils, cartridges normally can only be fitted in one kind of pencil body, and are made up of numerous components. This necessitates high technological requirements, causing much difficulty in assembly and mass-production. Besides, each kind of cartridge must go to its corresponding pencil body so that they are matched perfectly. This lack of interchangeability between a cartridge and a pencil body limits the using scope of automatic pencils.
Another disadvantage of such pencils is that during writing the lead has to be output by hand from time to time. What is worse, too much outputting may cause the lead to break while too little outputting may result in the scratching of paper.
Considering the above disadvantages of the prior art, an object of the invention is to provide an automatic pencil cartridge which has a compact and simple structure, can engage with pencil bodies having different shapes and automatically compensates the loss of lead during writing.